Each of Patent Documents 1 and 2 describes a process for producing 2-chloro-3-trifluoromethylpyridine by allowing 3-trifluoromethylpyridine to react with chlorine, but they were not always satisfactory from the standpoint of production rate of 2-chloro-3-trifluoromethylpyridine.
Non-Patent Document 1 describes a process for producing ethyl 2-chloro-3-pyridinecarboxylate by allowing 3-ethoxycarbonylpyridine N-oxide to react with phosphorus oxychloride, but it does not describe a production process of 2-chloro-3-trifluoromethylpyridine.